Forming of hollow articles



Nov. 9.192s; I T. E. MURRAY FORMING 0F HOLLOW ARTICLES Fi led June 20. 1924 2 sheetyshe'et @Mm'm MAI/fay T. E. MURRAY FORMING OF HOLLOW ARTICLES Filed June 20, 1924 Copper' Nov. 9 1926. 1,606,317

2 Sheets-Sheet 2 Fabric Patented Nov. 9, 1925.

THOMAS E. TvIURBAY, OF BROOKLYN, NE'W' YORK.

' FORMING OF HOLLOW ARTICLES.

Application filed June so,

In my application No. 679,521 and certain other pending applications, I have described the use, for forming ducts of con-' crete or the like, of a core of rubber or similar resilient, flexible material, such that drawahand when released itwill resume its original shape; the core being preferably used without mandrel or other reinforcingmeans, and being of such dimensions that rounding concrete.

it will support the ressure of the sur- 1 y present invention aims to utilize similar resilient, flexible cores in the moulding orshaping of hollow articlesot metal, or composed at least in part of metal. The accompanying drawings illustrate embodiments of the invention.

Fig. 1 illustrates a T or branch in a concrete body lined with metal and. formed by my present invention. 1

Fig. 2 illustrates in perspective the core and the metal lining for the structure of Fig. 1.

Fig. 3 illustrates inperspective the core alone.

Fig. 4 illustrates in perspective a core for a straight tube.

Figs. 5 to 9 illustrate 1n perspective suc-' cessive stages in the forming of an elbow of insulated metallic tubing.

Fig. 10 is an enlarged end view of Fig. 8.

In Fig. 1 a body of concrete 1 has a longitudinal duct connected with a lateral branch, the longitudinal and lateral portions being continuously lined with a thin coating or plate 2 of copper. In the making of such an article we start with a core shown in Fig. 3 and composed of two parts 3 and 4, held together by any suitable means along the line 5. These parts are made of rubber tubing of a highly resilient composition and with walls thick enough to stand all the strain to which they may be subjected, and thus to prevent deformation of the thin coating of copper referred to below. Such a core is coated with a layer or plate 6 (Fig. 2) of copper, which ultimatelyforms the lining 2 of the finished article. The metalmay be deposited electrolytically on the core. For this purpose the core 3 and should first be protected by an insulatin coating 7. Outside of this should be applie a layer of graphite 8 to take the deposit of metal 6. The metal-coated rubber core thus formed {side of the tubular concrete structure.

1924. Serial No. 721,181.

willthen be surrounded by concrete. The

nieces 3 and 4* of the rubber core will then e pulled out endwise. When the end of the core ispulled, the rubber is ext-ended lengthwise and contracted in cross-section.

so that it separates from the surrounding metal sufiicientlyto permit it to yield to-the pull and thus be withdrawn, leaving a very thin lining 2 of copper adhering to the in- The body of the article may be made of other material than concrete. The same is true of the metallic lining, which may be made of various metals capable of electric deposition. V

The invention may be applied also to the product of a simple metal article. For example, in Fig. 4' there is shown a rubber core 5 with a protective coating 7, graphite'S, and a deposited coating 9, consisting of a straight metal tube. The ends of the core are plugged with corks 10 during the deposition of the metal. The rubber core may be withdrawn, leaving merely a tube of metal operation.

The metal or other materials may be applied to the core'in various ways. In Fig. 9 I have illustrated a bent metal tube with a lining 11 of plastic or compound insulating material adapted to carry electric cables or wires. This may be made by the succession of a thickness'controllable in the electrolytic ofsteps illustrated in Figs. 5 to 8. A tubumaking similar insulation on electric cablestion with strips of rubber.

Outside of the coating of fabric or fabric Or the woven fabric may be-used in conjuncand plastic there are wound (Fig. 6) strips of very thin copper 1e overlapping one another. The tubular structure thus built up can be bent to any desired shape. Fig. 7 shows it bent to a simple elbow. The character of the materials is such that it will. bend easily and will maintain its bent shape. The form thus produced, in effect a com pound flexible mandrel, is then fixed in shape, as for example, by immersing in zinc 15 (Fig. 8) or in other metal or concrete, porcelain or the like.

The core 12 is then pulled, contracting it in cross section and separating it from the surrounding material and finally withdrawing it, leaving the tube (Fig. 9) with the lOO outer shelloi castzinc 15 aiid,the compound inner coating of textile,'plastic and copper indicated as a whole at 11. V

For some uses the outer heavy coating of zinc or other metal may be omitted... Also the wound copper may be omitted; the tubular structure of "fabric and plastic beingof such composition that it will stiffen sutiiciently for use, orbeing immersed in or treated with material which will stifle -it,

so as to permit the withdrawal ofthe resilient core. p Though I have described with great particularity of detail certain embodiments of my :invention,yet it is not-to be understood therefrom-that the invention is restricted to the particular embodiments; disclosed. i-Varims-modifications thereof. in detai hand in the arrangement of thegparts may be made a by those skilled in the art, withouhdeparture :from the invention as definedin the followl. The method ofmouldinghollow articles cles' compose-d at least .in part of metal,

which consists in shaping metal on a resilient core, forming, a body of vplast c, material around said metal and wlthdrawmg sald iamig metal as a lining in the body of plastic material.

4%. The method of moulding hollow arti- 'c-ls composed at least in part of metal, .wlnch conslstsin depositing metal on a re silient core, forming a body of: plastic material aroundsaid metal and withdrawing said core, leaving the metal as a thin lining in the body ofiplastic. material.

7 5. The method of moulding hollow articlesv which consistsin laying the material of such articles about a ,core of resilient vflexible material, bending the whole to the desired shape, fixing the 3 material in the desired shape and withdrawing said core.

6. The method of moulding hollow artifieiiible material, bending the whole to the desired shape, applyi g metal to the material to fix the shape and withdrawing the ore-vi a a a i. 1 1 a 7, The method'of moulding hollow articleswhich consists in laying insulating material about a core of resilient fleiiible materiah bending to the desired shape, applying metal to the insulating material and wlthdrawmg the core, leaving a tube of metalwith insulating lining.

8. The method of moul-dinghollow arti cles which consists of shaping flexible material to tubular forin on a resilient flexible core adapted when pulled lengthwise to con- .tractincross-section and thus separate from the surrounding material, stifiening said flexible material in the said tubular shape and pulling said core out of the surrounding material, j a y y In wvitness whereof, I have hereunto signed my name.

Thorn-is E. Ml JBR'AY.

' cles; which consists .in laying the material I orsnch art cles abouta core ofres1l1ent 

